Topic 10/20 Flashcards
Ethene + bromine chloride
Where does hydrogen go and wehre does chlorine go and what becomes carbocation
Most hydrogens accepts more positive halogen (Br) which has the most hydrogens and carbon with likely other carbons becomes carbocation and that is where cl goes
Trends in boiling point for organic compounds (7)
Alkane, halogenoalkane, aldehyde, ketone, amine, alcohol, carboxylic acid
Conformational vs configurational isomer
Conformational rotate around sigma bond and configurational occur in alkenes or cycoalknes and break and reform bond or rearrangement of stereocenter
Free radical substitution
Inition
Cl2 = 2ClR
propagation
CH4 + ClR = RCH3 + HCl
CH3R + Cl2 = CH3CL + ClR
Termination
ClR + ClR = Cl2
RCh3 + RCH3 = C2H6
Oxidation reactions and their OA
Primary alcohol, potassium dichromate
- If aldehyde, distillation, if carboxylic acid, reflux
Secondary alcohol, potassium dichomate
- To ketone
Alkyne to alkene
H2 and Pt
Alkene to alcohol
H20 and H2SO4
Carboxylic acid + alochol to ester
water
Nucleophillic substitutiion
Sn1 and Sn1
Electrophillic addition
Ethenes and breaking those bonds
Electrophillic substitution
Nitration of benzene
Solvents for Sn1 and Sn2
Polar protic and aproptic polar respectively
Why is hydroxide a better nucleophile than water?
More negative vs water is netural
Is Sn1 or Sn2 faster. Why?
Sn1, because only depends on concentration of one reactant
What ion is used in electrophillic substituion
No2+
Reduction reactions and their RA
Carboxlyic acid to primary alcohol, LiAlH4
Aldehydte to primary alcohol sodium borohydride
Ketone to secondary alcohol, sodium borohydride
Nitrobenzne to phenylamine
1) Tin and concentration HCL
2) Aqueous OH and heated under reflux
Define stereoisomer
Identical molecular and structural formula but different spatial arrangement of atoms
Has chiral carbon
Trends in boiling points (molar mass, branched chain, and functional group)
1) Molar mass increase, boiling point because stronger LDF
2) Branched chain are more spherical so less surface contact, thus weaker IMF and lower boiling points
3) Polar groups have stronger dipole dipole so higher boiling. Also OH and NH can form hydrogen bonds, explaining why amine, alcohol, and carboxylic acid
In which molecules are configurational isomers?
Alkenes and cyclic alkanes
Distinguish polar protic and aprotic polar solvent
polar protic have OH or NH so form hydrogen bonds, aprotic cannot form hydrogen bonds
Naming esters
Alcohol first and carboxlyic acid second (between O and ending in oate)
alcohol is on the outside
WHat is hydrogenation and what conditions does it occur?
Alkene and hydrogen gas, nickel catalyst
Reaction for combination of nitric and sulfuric acid for the nitration of benzene
2H2SO4 + HNO3 = NO2+ + 2HSO4- + H30+
Formula for calculating number of optical isomers
2n = where n = number of chiral centres
Which functional group is basic?
amine
Reasoning behind Markovnikov’s rule
Formation of more stable seconday/tertiary carbocation because of inductive effect because of extra alkyl group (s)
How to make nitrile from halogenalkane?
Halogenoalkane + cn- = nitrile + halogen ion
By Sn2 reaction
Colour change of bromine in test for unsaturation?
brown to colourless
Why does benzne undergo substitution more readily than addition?
Resonance makes carbon-carbon bonds too strong to break
How are primary, secondary and teritary amines classified?
Number of alkyl groups on the nitrogen
primary - 1 group
Heterolytic fission of chlorine
Electrophillic addition, and substitution for electrophillic and nucleophillic
Drawing stereoisomers using wedge-dash notation
Halogen is wedge and hydrogen is dash
